Hex key holder



FIG. 1 is a top, front, and left side perspective view of a hex key holder showing my new design, the broken-line disclosure of several hex key tools being for illustrative purposes only and forming no part of the claimed design;

FIG. 2 is a top plan view thereof, the bottom being a mirror image thereof;

FIG. 3 is a front elevational view thereof;

FIG. 4 is a left side elevational view thereof;

FIG. 5 is a right side elevational view thereof; and,

FIG. 6 is a rear elevational view thereof. 

The ornamental design for a hex key holder, as shown and described. 